Discontinued Operations - Assets and liabilities (Details) - USD ($) $ in Thousands	Oct. 27, 2018	Apr. 30, 2018
Balance Sheet
Accounts receivable, allowance for doubtful accounts (in dollars)	$ 1,054	$ 1,080
Total current assets classified as discontinued operations		25,668
Total current liabilities		9,294
EES Business | Discontinued Operations
Balance Sheet
Accounts receivable, net of allowance for doubtful accounts of $139 at April 30, 2018		6,889
Accounts receivable, allowance for doubtful accounts (in dollars)		139
Inventories, net		15,494
Prepaid expenses and other current assets		185
Property and equipment, current net		3,100
Total current assets classified as discontinued operations		25,668
Total assets classified as discontinued operations		25,668
Accounts payable		5,121
Wages and related accruals		1,946
Customer advances		1,028
Other current liabilities		1,199
Total current liabilities		9,294
Total liabilities classified as discontinued operations		$ 9,294